Air Quality and Emissions Progress Continues in 2013

National average air quality continues to improve as emissions decline through 2013.More Information...

Under the Clean Air Act, EPA establishes air quality standards
to protect public health and the environment. EPA has set national
air quality standards for six common air pollutants. These include:

carbon monoxide,

ozone,

lead,

nitrogen dioxide,

particulate matter (also
known as particle pollution), and

sulfur dioxide.

Each year EPA tracks the levels of these pollutants in the air and how much of each pollutant (or the pollutants that form them) is emitted from various pollution sources. The Agency looks at these numbers year after year to see how the pollutants have changed over time. EPA posts the results of our analyses to this web site.

Basic Information - Information about air quality standards for the six common air pollutants, also called criteria pollutants.